Quelle est en m/s la vitesse d'un outobus qui franchit une distance de 80km en 1h20mn.

Can anybody me with this? ? (picture included.)

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)

Which type of energy would have nothing to do with ironing clothes? a. heat b. chemical c. electrical d. mechanical